#include "Channel.h"
#include "EventLoop.h"
#include "Logger.h"

#include <sys/epoll.h>

const int Channel::kNoneEvent = 0;
const int Channel::kReadEvent = EPOLLIN | EPOLLPRI;
const int Channel::kWriteEvent = EPOLLOUT;

Channel::Channel(EventLoop* loop, int fd)
    : loop_(loop)
    , fd_(fd)
    , events_(0)
    , revents_(0)
    , index_(-1)
    , tied_(false)
{  
}

Channel::~Channel()
{
}

void Channel::tie(const std::shared_ptr<void>& obj)
{
    tie_ = obj;
    tied_ = true;
}

void Channel::update()
{
    // 通过channel所属的eventloop调用poller的相应方法,注册fd的event事件
    loop_->updateChannel(this);
}

// 在channel所属的eventloop中,把当前channel删除
void Channel::remove()
{
    loop_->removeChannel(this);
}

void Channel::handleEvent(Timestamp receiveTime)
{
    std::shared_ptr<void> guard;
    if(tied_)
    {
        guard = tie_.lock();
        if(guard)
        {
            handleEventWithGuard(receiveTime);
        }
    }
    else
    {
        handleEventWithGuard(receiveTime);
    }
}

// 根据poller通知的channel发生的具体事件,由channel负责调用具体的回调方法
void Channel::handleEventWithGuard(Timestamp receiveTime)
{
    LOG_INFO("channel handleEvent revents:%d", revents_);
    
    if((revents_ & EPOLLHUP) && !(revents_ & EPOLLIN))
    {
        if(closeCallback_)
        {
            closeCallback_();
        }
    }

    if(revents_ & (EPOLLERR))
    {
        if(errorCallback_)
        {
            errorCallback_();
        }
    }

    if(revents_ & (EPOLLIN | EPOLLPRI))
    {
        if(readCallback_)
        {
            readCallback_(receiveTime);
        }
    }

    if(revents_ & EPOLLOUT)
    {
        if(writeCallback_)
        {
            writeCallback_();
        }
    }
}